In recent years, a multimedia broadcast and multicast service in which data of content such as a music and an image are distributed from a data distributing device to a fixed terminal device has been used widely in a fixed terminal communication in a wired network. A broadcast communication in the fixed terminal communication is called “multichannel broadcasting” because a desired content can be selectively viewed among a lot of channels.
At the same time, a fusion of the fixed terminal communication and a mobile terminal communication called “fixed mobile convergence (FMC)” has been promoted. Moreover, a fusion of the fixed terminal communication, the mobile terminal communication, and a broadcast communication called “fixed mobile broadcast convergence (FMBC)” has been encouraged. In the context of such circumstances, the multimedia broadcast and multicast service (hereinafter abbreviated and referred to as “MBMS”) in which data of content such as music and images are distributed has been provided also in the mobile terminal communication, similarly to the fixed terminal communication.
However, the conventional technique has the following problems. Since a resource expansion is easy in the fixed terminal communication, the multichannel broadcasting can be easily achieved. On the other hand, limited radio resources are used to perform a communication between a mobile terminal and a base station in the MBMS in the mobile terminal communication. Therefore, there has been a problem that multichannel broadcasting in the number of channels over the number of the limited radio resources cannot be achieved and the number of channels is subjected to a limitation.
To prepare a lot of communication channels in the MBMS, a lot of radio resources (frequency and channelization code) for the number of communication channels come to be required. However, since the radio resources are limited, there has been a problem that an occupation of a majority of the radio resources for the MBMS weighs on radio resources to be used by a user for a normal verbal communication and a data transmission/reception and thereby a capacity in the number of users is decreased. More detailed information of the conventional technique as described above can be obtained in Japanese Laid-open Patent Publication No. 2004-40770.